I was driving in my car coming from Gilroy, California travelling east on highway 152 east halfway towards Interstate 5 opposite a very large reservoir as the full moon was out and the sky was clear. The CHP was investigating an apparent truck accident across the road when I saw three very bright white lights in triangle formation fly at a 180 degree angle which was flying sideways fly over the accident at about twenty miles an hour silently. There was no noise and the craft was flying at a very low altitude perhaps twenty feet above the ground and came right at me and straighted out and flew right over the hood of my car and it picked up speed and disappeared over the reservoir. At first I thought it may have been a life flight helicopter but this craft made no noise and my car window was open. I had the feeling the craft was friendly and was concerned about the accident.